Refrigerating apparatus employing carbonic acid.



No. 891,560. v PATENTED JUNE 23, 1908. F. E: MI TLLER.

REPRIGERATING APPARATUS EMPLOYING UARBONIG ACID.

APPLIOATION FILED APR. 29, 1907.

Witnesses: In ventgr:

' UNITED STATES PATENT OFFICE.

FRANZ EUGEN MULLER, or DRE'SDEN, GERMANY, AssIGNoa 'lQ BENNO KO'SSMANN, or

' COLOGNE, GERMANY.

REFRIGERATING APPARATUS EMPLOYING CARBONIC ACID.

Specification of Letters Patent.

Patented June 23, 1908.

Application filed April 29, 1907. I Serial No. 370,884.

T all whom it may concern:

Be it known that I, FRANZ EUGEN MULLER, engineer, subject of the German Emperor, residing at Dresden, Germany, have invented new and useful Improvements in Refrigerating Apparatus Employing Carbonic Acid of which the'following is a specification.

This invention relates to a refrigerating apparatus which is adapted for use in any household, and especially, in hotels, restaurants, hospitals, on shipboard and the like.

The apparatus is ada ted for making fruit ices, cooling foods, drin s and the like and as experiments have shown enables the desired refrigeratin action to be extremely rapidly obtained, w ile it is alsoextremely simple to handle, so that the making of fruit ices for instance requires only from 1 to 2 minutes of time, and water maybe congealed in one minute, and so forth.

An example of construction of the apparatus 1s shown in the accompanying drawings in which Figure 1 is a vertical section of the apparatus; and Fig. 2, a view partly in section showing the valve; and Fig. 3, a plan View.

The invention consists in means for obtaining in a refrigerating apparatus operated with carbonic acid, the greatest possible result with the carbonic acidand a practical production of the frozen substances. The carbonic acid introduced into the tightly closed refrigerating chamber of the apparatus after having produced the low temperature by its expansion in its passage through the substances to be frozen, is conveyed on escaping from the refrigerating chamber to one of the chambers which entirely inclose the former, in which outer chamber it can further expand and cause a further cooling of the refrigerating chamber. The thereby increased cooling action is further assisted by the outlet aperture through which the carbonic acid leaves the apparatus being if desired providedwitha sprin weighted valve (flap valve or the like), w ereby the escaping carbonic acid is throttled and thus its violent escape moderated. The carbonic acid is consequently compelled to act more intensively in the chamber of the refrigerator so that the consumption of carbonic acid is very small and the refrigerating apparatus is, economical in working. The escaping carbonic acid may if desired be also further utilized for instance in the manufacture of mineral water or the like.

The apparatus consists of an actual refrigerating chamber 0. which is inclosed in a large case b in such a way that a hollow chamber 0 remains all around and at the bottom. A jacket (1 is also provided round the external walls of the chamber 1) and the interstice a bad conductor of heat in order .to avoid loss of cold.

One of the ordinary steel bottles filled with carbonic acid is connected with the outer end of a pipe f, the inner end of which pipe con-. nects with the lower part of the refrigerating chamber a in proximity to the bottom of the latter. When the valve of the bottle is opened, the carbonic acid enters the lower art of the refrigerating chamber. The atter contains the substance or substances to be refrigerated and is hermetically closed. above by means of a removable cover or lid g The carbonic acid which expands in its assage through the substance to be frozen mside the refrigerating chamber and thereby produces intense cold, escapes at the upper end of the chamber through a pipe h located in the cover and through a bent pi e i inserted therein, into the chamber 0 which surrounds the refrigerating chamber a i on all sides and at the bottom. Within this chamber c the carbonic acid can further expand and flow round all sides of the refrigerating ohalmger so that the latter is still further coo e thus formed is filled with a material which is The carbonic acid escapes from the chainber c throu h an aperture k (Fig. 2) on-which a preferab y external valve is provided which closes automatically either by the pressure of a spring or by its own weight and thus opposes a certain resistance to the. escapin carbonic acid. The carbonic acid vis there y throttled and its violent escape ing vessel is preferab y formed as a cap 111 order to (prevent the vigorously rising carbonic aci carrying with it into the pipe, h,

l and chamber 0 portions of the contents,

which are to be refrigerated, of the vessel a.

-I declare that whatI claim is:

1. A refrigerating apparatus comprising an inner vessel, a cover therefor, ,an outer vessel having heat non-conductin walls, forming a space between itself and t e inner vessel, means for introducing carbonic acid into the inner vessel, a pipe'leading from the top of the inner vessel through the walls of the outer vessel to the said s ace and a valve controlled pipe in the wa s of the outer vessel connecting the. space with the atmosphere.

2. A freezing apparatus, comprising an outer vessel, a freezing cell and means for introducing carbonic acid into the freezing cell' near the bottom thereof where it expands at first within the latter, and then flows directly through the substance to be frozen, then flows into the shallow space between -the vessel andcell and which surrounds the freezing cell from all sides so that the acid in that way comes in contact with the whole freezing cell and the walls thereof from the inside as well as from the outside, in order to attain an intense frigidity.

In testimony whereof I have signed my, 

